MBR (Master Boot Record) partition table is a traditional way of MS-DOS to partition larger hard disc drives into distinct partitions.
This table is stored in the end of the boot sector (first sector) of the drive, after the bootstrap code. Original DOS 2.0 specification allowed only 4 partitions per disc, but DOS 3.2 introduced concept of "extended partitions", which work as nested extra "boot records" which are pointed to by original ("primary") partitions in MBR.
This page hosts a formal specification of MBR (Master Boot Record) partition table using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.
The Python runtime library can be installed from PyPI:
python3 -m pip install kaitaistructParse a local file and get structure in memory:
data = MbrPartitionTable.from_file("path/to/local/file.bin")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = MbrPartitionTable(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.bootstrap_code # => get bootstrap code
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 9):
raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))
class MbrPartitionTable(KaitaiStruct):
"""MBR (Master Boot Record) partition table is a traditional way of
MS-DOS to partition larger hard disc drives into distinct
partitions.
This table is stored in the end of the boot sector (first sector) of
the drive, after the bootstrap code. Original DOS 2.0 specification
allowed only 4 partitions per disc, but DOS 3.2 introduced concept
of "extended partitions", which work as nested extra "boot records"
which are pointed to by original ("primary") partitions in MBR.
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.bootstrap_code = self._io.read_bytes(446)
self.partitions = []
for i in range(4):
self.partitions.append(MbrPartitionTable.PartitionEntry(self._io, self, self._root))
self.boot_signature = self._io.read_bytes(2)
if not self.boot_signature == b"\x55\xAA":
raise kaitaistruct.ValidationNotEqualError(b"\x55\xAA", self.boot_signature, self._io, u"/seq/2")
class PartitionEntry(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.status = self._io.read_u1()
self.chs_start = MbrPartitionTable.Chs(self._io, self, self._root)
self.partition_type = self._io.read_u1()
self.chs_end = MbrPartitionTable.Chs(self._io, self, self._root)
self.lba_start = self._io.read_u4le()
self.num_sectors = self._io.read_u4le()
class Chs(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.head = self._io.read_u1()
self.b2 = self._io.read_u1()
self.b3 = self._io.read_u1()
@property
def sector(self):
if hasattr(self, '_m_sector'):
return self._m_sector
self._m_sector = (self.b2 & 63)
return getattr(self, '_m_sector', None)
@property
def cylinder(self):
if hasattr(self, '_m_cylinder'):
return self._m_cylinder
self._m_cylinder = (self.b3 + ((self.b2 & 192) << 2))
return getattr(self, '_m_cylinder', None)